Stepping device



May 29, 1951 H. w. GOFF 2,554,981

STEPPING DEVICE Filed Nov. 8, 1947 /N VEN TOR %;GOFF By A from/5f( atented May 29, 1951 u-uNlTfiIezaD l'S'IEPPING DEVICE :Harold W.- Golf, '.ManhasseLtN.v Y.,.=assignor to Bell TelephoneLaboratories, Incorporated, New v.Yox-k, N ...Y.,a corporation of New York `YAliplicaattion'November 8, 19'47; Serial No. 784,845

y 9.Claims. A)1 invention relates tok stepping devices or devices :for 'producing intermittent motion.

In some types of apparatus,- for example-the recording device disclosed'in the copendingfapplication of W. W, CarpenterSerial'No. 588,401, led A April 14, 1945, a drumforother part .is rotated or otherwise movedinsuccessive discrete steps. may be done byl various `well-known `mechanical means, such as a ratchetzand pawl. Howevenfon account ofithe inertia vof the part `moved, itis necessary'not vonly to: start it for each. steplbut alsofto larrestit at the'endof each step. .Mechanical devices can give ample power to move .the part,.but when .also rused asstartingandstopping means, they tend -tobe ,noisy and to wear l rapidly.

.I ypropose -to use lmagnetic devices for starting and stopping the. part to be stepped. In --these thereisno physical contact betweenmoving and stationary partsand,v therefore, there can be no noise. or wear of vthe partssincident to the sudden starting and stopping-of the mechanism.

' The features of my invention and its modeof operation `will Vbe yapparent from the .accompanying `description, .the appended -claims and the drawing which `shows*theinvention applied VVto the rotation in steps of a drum., suchas Athedrum of the recordingdev'lice referred `to above.

`In "the drawingfDl isthe recorder drum. tobe rotated' in successive steps. Fixed tothe drum D- lis" the worm wheel WW- inengagement with the worm `W on shaft'S. wFixed to .shaft S. is-a cam C 'having two lobesadapted to engage the discv DC which is continuously rotated, by any siitable means, to furnish "the driving powerjfor the' mechanism. The Ytwoflobes of cam 'C.are f such v'dimensions that, upon rotation of cam-.C, each of 'said lobesfrictionally engages theperiphery of discDC for somewhatless than one-half a revolution of cam C. .Fixed ftoshaft `sare-two rotors R and RI lof .magnetic material eachhaving twopoles adaptedv to rotate with smallciearance Abetween the pole-.pieces -of the respective magnets M and yMI. "'A-commutator CM fofrinsulating material having -two .diametrically opposed 4inserts-#I and AII ofv conductingfmarial each adapted to 'engage rthe twocontact springs CT- and CTI simultaneously, risfalso fixed to shaft S. y.The angular relation'on shaft S .ofthe parts C,--R, RI and VCMvfis such that, when neither llof the lobes of cam rC'fisin Vcontact with-disc DC, fthe poles of rotor R are in :line'with Athe vpole-pieces ofdmagnet M, one of the inserts ofocommutator is in -contact with' both r contact 'springs CT and-CTI vand the-poles off rotor; `RI tare nearly 2 but not quite .in line .with .the pole-pieces of magnet MI.

yAssuming .that the parts, except. .disc DCV-are at` rest in the positions shown in'thedrawing and it is desired to `cause the drumD to step; switch SW is openedand. switch SW I closed :by any suitable means. With switch SWopen, magnet Mrisdeenergized. By theclosu-re of switchLSWI, ascircuit is -completed Ifrom' battery throughxthe winding lof magnet MI, switch :SWL 'contact spring- CT, insert I of commutator CM,` and contact-'spring CTI to battery,'senergizing magnet MI which. attracts the poles of rotor` .-RI, thereby partially rotating shaft Sin the direction'ofthe arrow .aroundsaid shaft. Oneof the lobesof cam C then Vmakes fric'tional vcontact .withrdi-sc DC `and cam C is thereby rotated, rotating, through shaft `S, worm W, and wormwheelfwW. the'd-rum D. As shaft S rotates,insert I of commutator CM passes vout of 'contactwith Contact springsCTand CTI, opening the circuit of and deenergizing magnetMI. Switch-SW is now vreclosed and switch vSWI opened by any suitable means. Byv the closure of :switch SW, the circuit of. .magnet M is completed and saidmagnet-energized. When the lobe of cam Cl ceases to make contact with -disc DC, the :attraction of :magnet M .for 'the poles `of rotor R'arrests further rotation of shaft S` and; therefore, of .drum D. The shaft S will athen have made one-half .afrevolution and drumD'will have rotated afpropcrtional amount. The action may then be repeatedinia.

similar manner for' the other half vi-evolutionfof shaft SLusing the. 'other .lobe of tcam C'. and .insert II :of commutator CM. Thus v.byzmanipulaticn of-L'switches SW. and SWIgasfdescribed.above, shaft S vmay be caused to fmake successive :half revolutions anddrurn D 'rotated .in corresponding steps. The attractionof magnet Mier-the Ypol'esfof rotor .R may be made stronger 'than 4the attrac tionof magnetMI forl the poles of RI. Then switch .SWI may be left `permanently Vclosed. With switch .SW.closed, .shaft S will be held against .rotation byv the .attraction `of magnet-M for the poles.iofrotor"R. WhenIlswit'ch''SWrsis opened, shaftS is then turned bythe attraction of magnet MI for thepoles of rotor RI: and-the cycle of operations .described .above 'takes' place. Commutator CM is a convenient .means of opening 'the circuit vof magnet MI whensaid magnet has performed its function of initiating the'rotation.ofshaftS However, Aif desiredrsaid commutatorv may be omitted'andthe circuit of magnet M-I @controlled by 'switch SWI alone.

For convenience, shaft S is shown connected to drum D by worm W and worm wheel WW. Drum D may, however, be mounted directly on shaft S or, alternately, all of the parts C, R. RI and CM may be mounted on drum D itself or otherwise attached thereto. While the invention has been shown as applied to the control of the record-feed drum of a recording device, it is obvious that it may equally well be applied to similar drums of other devices. Furthermore, it is obvious to one skilled in the art that the rotation of shaft S may be utilized, by suitable wellknown means, to control the movement of parts other than drums and for movements of translation as well as of rotation.

What is claimed is:

1. In combination, a movable load, driving means therefor normally disconnected therefrom, magnetic means for initiating movement of said load, coupling means effective after the beginning of said initial movement for connecting said load with said driving means, thereby to impart continued movement to said load for a predetermined amount of said movement, and magnetic means effective subsequent to the uncoupling of said load from said driving means for arresting the movement of said load.

2; In combination, a rotatable shaft, driving means for said shaft normally disconnected therefrom, magnetic means for initiating the rotation of said shaft, coupling means effective after the beginning of said initial rotation for connecting said'shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of said rotation, and magnetic means effective subsequent to the uncoupling of said shaft from said driving means for arresting the rotation of said shaft.

3. In combination, a rotatable shaft, driving means for said shaft normally disconnected therefrom, a first magnet, a first rotor on said shaft responsive to said rst magnet for initiating'rotation of said shaft, coupling means effective after the beginning of said initial rotation for 'connecting said shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of said rotation, a second magnet, and a second rotor on said shaft responsive to said second magnet and effective subsequent to the uncoupling of said shaft from said driving means for arresting rotation of said shaft.

4. A stepping device comprising in combination, a part to be moved in successive steps, driving means for said part normally disconnected therefrom, a first magnetic device for initiating the movement of each step of said part, coupling means effective after the beginning of an initial movement of said part for connecting said part to said driving means, thereby to impart continued movement to said part for the predetermined amount of said movement necessary to complete a step, and a second magnetic device effective subsequent to the uncoupling of said part from said driving means for arresting the movement of each step of said part.

5. In a recording device, a rotatable recordfeed drum, a rotatable shaft, driving means for said shaft normally disconnecting therefrom, a first magnetic device for repeatedly initiating rotation of said shaft, coupling means effective after the beginning of each initial rotation for connecting said shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of said movement, a sec- '4 ond magnetic device effective subsequent to the uncoupling of said shaft from said driving means for arresting each rotation of said shaft, and means connecting said shaft with said drum whereby rotation is imparted to said drum by any rotation of said shaft.

6. In a recording device, a rotatable recordfeed drum, a rotatable shaft, driving means for said shaft normally disconnected therefrom, a first magnet, a rst rotor on said shaft responsive to said first magnet to repeatedly initiate rotation of said shaft, coupling means effective after the beginning of each initial rotation for connecting said shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of said movement, a second magnet, a second rotor on said shaft responsive to said second magnet and effective subsequent to the uncoupling of said shaft from said driving means for arresting each rotation of said shaft, and means connecting said shaft with said drum, whereby rotation is imparted to said drum by any rotation of said shaft.

7. In a recording device, a rotatable recordfeed drum having thereon a plurality of equally spaced recording positions, a rotatable shaft, driving means for said shaft normally disconnected therefrom, a first magnetic means for repeatedly initiating rotation of said shaft, coupling means effective after the beginning of eachinitial rotation for connecting said shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of movement indicative of the separation between any two recording positions on said drum, a second magnetic means effective subsequent to the uncoupling of said shaft from said driving means for arresting each rotation of said shaft, and means connecting said shaft with said record-feed drum effective to impart rotation to said drum by the rotation of said shaft, thereby to advance said drum to a succeeding recording position.

8. In a recording device, a rotatable recordfeed drum having thereon a plurality of equally spaced recording positions, a rotatable shaft, driving means for said shaft normally disconnected therefrom, a first magnet, a rotor on said shaft responsive to said first magnet for repeatedly initiating rotation of said shaft, coupling means effective after the beginning of each initial rotation for connecting said shaft with said driving means, thereby to impart continued rotation to said shaft for a predetermined amount of movement indicative of the separation between any two recording positions on said drum, a second magnet, a second rotor responsive to said sec` ond magnet and effective subsequent to the uncoupling of said shaft from said driving means for arresting each rotation of said shaft, and means connecting said shaft with said record-feed drum effective to impart rotation to said drum by the rotation of said shaft, thereby to advance said drum t0 a succeeding recording position.

9. In a recording device, a record-feed drum having thereon a plurality of equally spaced recording positions, and means for rotating said' drum in successive steps to each of said recording positions, comprising a first control means, a first magnetic device responsive to said control means to initiate successive rotative steps of said drum, a frictional device effective only after each initial rotation of said drum for continuing said rotation for an amount that will rotate said drum to the next recording position, a second control means, and a second magnetic device responsive to said second control means to arrest each successive rotation of said drum at each of said recording positions.

HAROLD W. GOFF.

REFERENCES CITED The following references are of record in the file of this patent:

Number 6 UNITED STATES PATENTS* Name Date Titterington Oct. 30, 1923 Langsdorf June 11, 1929 

